👉 Antibodies, also known as immunoglobulins, are Y-shaped proteins produced by B cells in response to foreign antigens, such as viruses or bacteria. These molecules are critical components of the adaptive immune system, functioning to recognize and bind specifically to antigens with high precision. The "arms" of the antibody's Y-shape consist of two identical heavy chains and two identical light chains, forming a structure that can lock onto an antigen through complementary shapes and chemical interactions. Each antibody has unique antigen-binding sites, known as paratopes, which are tailored to match the specific epitope of the antigen. This binding not only neutralizes or marks the antigen for destruction by other immune cells but also initiates various immune responses, including complement activation and antibody-dependent cellular cytotoxicity. Thus, antibodies play a pivotal role in identifying and neutralizing pathogens, thereby protecting the body from infections.
